package org.ngame.socket.util;

/**
 * <p>Encodes and decodes to and from Base64 notation.</p> <p>Homepage: <a
 * href="http://iharder.net/base64">http://iharder.net/base64</a>.</p>
 *
 * <p>Example:</p>
 *
 * <code>String encoded = Base64.encode( myByteArray );</code> <br />
 * <code>byte[] myByteArray = Base64.decode( encoded );</code>
 *
 * <p>The <tt>options</tt> parameter, which appears in a few places, is used to
 * pass several pieces of information to the encoder. In the "higher level"
 * methods such as encodeBytes( bytes, options ) the options parameter can be
 * used to indicate such things as first gzipping the bytes before encoding
 * them, not inserting linefeeds, and encoding using the URL-safe and Ordered
 * dialects.</p>
 *
 * <p>Note, according to <a
 * href="http://www.faqs.org/rfcs/rfc3548.html">RFC3548</a>, Section 2.1,
 * implementations should not add line feeds unless explicitly told to do so.
 * I've got Base64 set to this behavior now, although earlier versions broke
 * lines by default.</p>
 *
 * <p>The constants defined in Base64 can be OR-ed together to combine options,
 * so you might make a call like this:</p>
 *
 * <code>String encoded = Base64.encodeBytes( mybytes, Base64.GZIP | Base64.DO_BREAK_LINES );</code>
 * <p>to compress the data before encoding it and then making the output have
 * newline characters.</p> <p>Also...</p>
 * <code>String encoded = Base64.encodeBytes( crazyString.getBytes() );</code>
 *
 *
 *
 * <p> Change Log: </p> <ul> <li>v2.3.7 - Fixed subtle bug when base 64 input
 * stream contained the value 01111111, which is an invalid base 64 character
 * but should not throw an ArrayIndexOutOfBoundsException either. Led to
 * discovery of mishandling (or potential for better handling) of other bad
 * input characters. You should now get an IOException if you try decoding
 * something that has bad characters in it.</li> <li>v2.3.6 - Fixed bug when
 * breaking lines and the final byte of the encoded string ended in the last
 * column; the buffer was not properly shrunk and contained an extra (null) byte
 * that made it into the string.</li> <li>v2.3.5 - Fixed bug in
 * {@link #encodeFromFile} where estimated buffer size was wrong for files of
 * size 31, 34, and 37 bytes.</li> <li>v2.3.4 - Fixed bug when working with
 * gzipped streams whereby flushing the Base64.OutputStream closed the Base64
 * encoding (by padding with equals signs) too soon. Also added an option to
 * suppress the automatic decoding of gzipped streams. Also added experimental
 * support for specifying a class loader when using the
 * {@link #decodeToObject(java.lang.String, int, java.lang.ClassLoader)}
 * method.</li> <li>v2.3.3 - Changed default char encoding to US-ASCII which
 * reduces the internal Java footprint with its CharEncoders and so forth. Fixed
 * some javadocs that were inconsistent. Removed imports and specified things
 * like java.io.IOException explicitly inline.</li> <li>v2.3.2 - Reduced memory
 * footprint! Finally refined the "guessing" of how big the final encoded data
 * will be so that the code doesn't have to create two output arrays: an
 * oversized initial one and then a final, exact-sized one. Big win when using
 * the {@link #encodeBytesToBytes(byte[])} family of methods (and not using the
 * gzip options which uses a different mechanism with streams and stuff).</li>
 * <li>v2.3.1 - Added {@link #encodeBytesToBytes(byte[], int, int, int)} and
 * some similar helper methods to be more efficient with memory by not returning
 * a String but just a byte array.</li> <li>v2.3 - <strong>This is not a drop-in
 * replacement!</strong> This is two years of comments and bug fixes queued up
 * and finally executed. Thanks to everyone who sent me stuff, and I'm sorry I
 * wasn't able to distribute your fixes to everyone else. Much bad coding was
 * cleaned up including throwing exceptions where necessary instead of returning
 * null values or something similar. Here are some changes that may affect you:
 * <ul> <li><em>Does not break lines, by default.</em> This is to keep in
 * compliance with <a
 * href="http://www.faqs.org/rfcs/rfc3548.html">RFC3548</a>.</li> <li><em>Throws
 * exceptions instead of returning null values.</em> Because some operations
 * (especially those that may permit the GZIP option) use IO streams, there is a
 * possiblity of an java.io.IOException being thrown. After some discussion and
 * thought, I've changed the behavior of the methods to throw
 * java.io.IOExceptions rather than return null if ever there's an error. I
 * think this is more appropriate, though it will require some changes to your
 * code. Sorry, it should have been done this way to begin with.</li>
 * <li><em>Removed all references to System.out, System.err, and the like.</em>
 * Shame on me. All I can say is sorry they were ever there.</li> <li><em>Throws
 * NullPointerExceptions and IllegalArgumentExceptions</em> as needed such as
 * when passed arrays are null or offsets are invalid.</li> <li>Cleaned up as
 * much javadoc as I could to avoid any javadoc warnings. This was especially
 * annoying before for people who were thorough in their own projects and then
 * had gobs of javadoc warnings on this file.</li> </ul> <li>v2.2.1 - Fixed bug
 * using URL_SAFE and ORDERED encodings. Fixed bug when using very small files
 * (~&lt; 40 bytes).</li> <li>v2.2 - Added some helper methods for
 * encoding/decoding directly from one file to the next. Also added a main()
 * method to support command line encoding/decoding from one file to the next.
 * Also added these Base64 dialects: <ol> <li>The default is RFC3548
 * format.</li> <li>Calling
 * Base64.setFormat(Base64.BASE64_FORMAT.URLSAFE_FORMAT) generates URL and file
 * name friendly format as described in Section 4 of RFC3548.
 * http://www.faqs.org/rfcs/rfc3548.html</li> <li>Calling
 * Base64.setFormat(Base64.BASE64_FORMAT.ORDERED_FORMAT) generates URL and file
 * name friendly format that preserves lexical ordering as described in
 * http://www.faqs.org/qa/rfcc-1940.html</li> </ol> Special thanks to Jim
 * Kellerman at <a href="http://www.powerset.com/">http://www.powerset.com/</a>
 * for contributing the new Base64 dialects. </li>
 *
 * <li>v2.1 - Cleaned up javadoc comments and unused variables and methods.
 * Added some convenience methods for reading and writing to and from
 * files.</li> <li>v2.0.2 - Now specifies UTF-8 encoding in places where the
 * code fails on systems with other encodings (like EBCDIC).</li> <li>v2.0.1 -
 * Fixed an error when decoding a single byte, that is, when the encoded data
 * was a single byte.</li> <li>v2.0 - I got rid of methods that used booleans to
 * set options. Now everything is more consolidated and cleaner. The code now
 * detects when data that's being decoded is gzip-compressed and will decompress
 * it automatically. Generally things are cleaner. You'll probably have to
 * change some method calls that you were making to support the new options
 * format (<tt>int</tt>s that you "OR" together).</li> <li>v1.5.1 - Fixed bug
 * when decompressing and decoding to a byte[] using <tt>decode( String s,
 * boolean gzipCompressed )</tt>. Added the ability to "suspend" encoding in the
 * Output Stream so you can turn on and off the encoding if you need to embed
 * base64 data in an otherwise "normal" stream (like an XML file).</li> <li>v1.5
 * - Output stream pases on flush() command but doesn't do anything itself. This
 * helps when using GZIP streams. Added the ability to GZip-compress objects
 * before encoding them.</li> <li>v1.4 - Added helper methods to read/write
 * files.</li> <li>v1.3.6 - Fixed OutputStream.flush() so that 'position' is
 * reset.</li> <li>v1.3.5 - Added flag to turn on and off line breaks. Fixed bug
 * in input stream where last buffer being read, if not completely full, was not
 * returned.</li> <li>v1.3.4 - Fixed when "improperly padded stream" error was
 * thrown at the wrong time.</li> <li>v1.3.3 - Fixed I/O streams which were
 * totally messed up.</li> </ul>
 *
 * <p> I am placing this code in the Public Domain. Do with it as you will. This
 * software comes with no guarantees or warranties but with plenty of
 * well-wishing instead! Please visit <a
 * href="http://iharder.net/base64">http://iharder.net/base64</a> periodically
 * to check for updates or to contribute improvements. </p>
 *
 * @author Robert Harder
 * @author rob@iharder.net
 * @version 2.3.7
 */
public class Base64
{

    /*
     * ******** P U B L I C F I E L D S ********
     */
    /**
     * No options specified. Value is zero.
     */
    public final static int NO_OPTIONS = 0;
    /**
     * Specify encoding in first bit. Value is one.
     */
    public final static int ENCODE = 1;
    /**
     * Specify decoding in first bit. Value is zero.
     */
    public final static int DECODE = 0;
    /**
     * Specify that data should be gzip-compressed in second bit. Value is two.
     */
    public final static int GZIP = 2;
    /**
     * Specify that gzipped data should <em>not</em> be automatically gunzipped.
     */
    public final static int DONT_GUNZIP = 4;
    /**
     * Do break lines when encoding. Value is 8.
     */
    public final static int DO_BREAK_LINES = 8;
    /**
     * Encode using Base64-like encoding that is URL- and Filename-safe as
     * described in Section 4 of RFC3548: <a
     * href="http://www.faqs.org/rfcs/rfc3548.html">http://www.faqs.org/rfcs/rfc3548.html</a>.
     * It is important to note that data encoded this way is <em>not</em>
     * officially valid Base64, or at the very least should not be called Base64
     * without also specifying that is was encoded using the URL- and
     * Filename-safe dialect.
     */
    public final static int URL_SAFE = 16;
    /**
     * Encode using the special "ordered" dialect of Base64 described here: <a
     * href="http://www.faqs.org/qa/rfcc-1940.html">http://www.faqs.org/qa/rfcc-1940.html</a>.
     */
    public final static int ORDERED = 32;
    /*
     * ******** P R I V A T E F I E L D S ********
     */
    /**
     * Maximum line length (76) of Base64 output.
     */
    private final static int MAX_LINE_LENGTH = 76;
    /**
     * The equals sign (=) as a byte.
     */
    private final static byte EQUALS_SIGN = (byte) '=';
    /**
     * The new line character (\n) as a byte.
     */
    private final static byte NEW_LINE = (byte) '\n';
    /**
     * Preferred encoding.
     */
    private final static String PREFERRED_ENCODING = "US-ASCII";
    private final static byte WHITE_SPACE_ENC = -5; // Indicates white space in encoding
    private final static byte EQUALS_SIGN_ENC = -1; // Indicates equals sign in encoding
    /*
     * ******** S T A N D A R D B A S E 6 4 A L P H A B E T ********
     */
    /**
     * The 64 valid Base64 values.
     */
    /*
     * Host platform me be something funny like EBCDIC, so we hardcode these
     * values.
     */
    private final static byte[] _STANDARD_ALPHABET =
    {
        (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F', (byte) 'G',
        (byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N',
        (byte) 'O', (byte) 'P', (byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U',
        (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z',
        (byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g',
        (byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n',
        (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't', (byte) 'u',
        (byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z',
        (byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4', (byte) '5',
        (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) '+', (byte) '/'
    };
    /**
     * Translates a Base64 value to either its 6-bit reconstruction value or a
     * negative number indicating some other meaning.
     *
     */
    private final static byte[] _STANDARD_DECODABET =
    {
        -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal  0 -  8
        -5, -5, // Whitespace: Tab and Linefeed
        -9, -9, // Decimal 11 - 12
        -5, // Whitespace: Carriage Return
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 - 26
        -9, -9, -9, -9, -9, // Decimal 27 - 31
        -5, // Whitespace: Space
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 42
        62, // Plus sign at decimal 43
        -9, -9, -9, // Decimal 44 - 46
        63, // Slash at decimal 47
        52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // Numbers zero through nine
        -9, -9, -9, // Decimal 58 - 60
        -1, // Equals sign at decimal 61
        -9, -9, -9, // Decimal 62 - 64
        0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, // Letters 'A' through 'N'
        14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // Letters 'O' through 'Z'
        -9, -9, -9, -9, -9, -9, // Decimal 91 - 96
        26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, // Letters 'a' through 'm'
        39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // Letters 'n' through 'z'
        -9, -9, -9, -9, -9 // Decimal 123 - 127
        , -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 128 - 139
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 140 - 152
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 153 - 165
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 166 - 178
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 179 - 191
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 192 - 204
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 205 - 217
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 218 - 230
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 231 - 243
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9         // Decimal 244 - 255 
    };
    /*
     * ******** U R L S A F E B A S E 6 4 A L P H A B E T ********
     */
    /**
     * Used in the URL- and Filename-safe dialect described in Section 4 of
     * RFC3548: <a
     * href="http://www.faqs.org/rfcs/rfc3548.html">http://www.faqs.org/rfcs/rfc3548.html</a>.
     * Notice that the last two bytes become "hyphen" and "underscore" instead
     * of "plus" and "slash."
     */
    private final static byte[] _URL_SAFE_ALPHABET =
    {
        (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F', (byte) 'G',
        (byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N',
        (byte) 'O', (byte) 'P', (byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U',
        (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z',
        (byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g',
        (byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n',
        (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't', (byte) 'u',
        (byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z',
        (byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4', (byte) '5',
        (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) '-', (byte) '_'
    };
    /**
     * Used in decoding URL- and Filename-safe dialects of Base64.
     */
    private final static byte[] _URL_SAFE_DECODABET =
    {
        -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal  0 -  8
        -5, -5, // Whitespace: Tab and Linefeed
        -9, -9, // Decimal 11 - 12
        -5, // Whitespace: Carriage Return
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 - 26
        -9, -9, -9, -9, -9, // Decimal 27 - 31
        -5, // Whitespace: Space
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 42
        -9, // Plus sign at decimal 43
        -9, // Decimal 44
        62, // Minus sign at decimal 45
        -9, // Decimal 46
        -9, // Slash at decimal 47
        52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // Numbers zero through nine
        -9, -9, -9, // Decimal 58 - 60
        -1, // Equals sign at decimal 61
        -9, -9, -9, // Decimal 62 - 64
        0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, // Letters 'A' through 'N'
        14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // Letters 'O' through 'Z'
        -9, -9, -9, -9, // Decimal 91 - 94
        63, // Underscore at decimal 95
        -9, // Decimal 96
        26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, // Letters 'a' through 'm'
        39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // Letters 'n' through 'z'
        -9, -9, -9, -9, -9 // Decimal 123 - 127
        , -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 128 - 139
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 140 - 152
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 153 - 165
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 166 - 178
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 179 - 191
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 192 - 204
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 205 - 217
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 218 - 230
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 231 - 243
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9         // Decimal 244 - 255 
    };
    /*
     * ******** O R D E R E D B A S E 6 4 A L P H A B E T ********
     */
    /**
     * I don't get the point of this technique, but someone requested it, and it
     * is described here: <a
     * href="http://www.faqs.org/qa/rfcc-1940.html">http://www.faqs.org/qa/rfcc-1940.html</a>.
     */
    private final static byte[] _ORDERED_ALPHABET =
    {
        (byte) '-',
        (byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4',
        (byte) '5', (byte) '6', (byte) '7', (byte) '8', (byte) '9',
        (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F', (byte) 'G',
        (byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N',
        (byte) 'O', (byte) 'P', (byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U',
        (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z',
        (byte) '_',
        (byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g',
        (byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n',
        (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't', (byte) 'u',
        (byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z'
    };
    /**
     * Used in decoding the "ordered" dialect of Base64.
     */
    private final static byte[] _ORDERED_DECODABET =
    {
        -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal  0 -  8
        -5, -5, // Whitespace: Tab and Linefeed
        -9, -9, // Decimal 11 - 12
        -5, // Whitespace: Carriage Return
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 - 26
        -9, -9, -9, -9, -9, // Decimal 27 - 31
        -5, // Whitespace: Space
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 42
        -9, // Plus sign at decimal 43
        -9, // Decimal 44
        0, // Minus sign at decimal 45
        -9, // Decimal 46
        -9, // Slash at decimal 47
        1, 2, 3, 4, 5, 6, 7, 8, 9, 10, // Numbers zero through nine
        -9, -9, -9, // Decimal 58 - 60
        -1, // Equals sign at decimal 61
        -9, -9, -9, // Decimal 62 - 64
        11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, // Letters 'A' through 'M'
        24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, // Letters 'N' through 'Z'
        -9, -9, -9, -9, // Decimal 91 - 94
        37, // Underscore at decimal 95
        -9, // Decimal 96
        38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, // Letters 'a' through 'm'
        51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, // Letters 'n' through 'z'
        -9, -9, -9, -9, -9 // Decimal 123 - 127
        , -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 128 - 139
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 140 - 152
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 153 - 165
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 166 - 178
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 179 - 191
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 192 - 204
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 205 - 217
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 218 - 230
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 231 - 243
        -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9         // Decimal 244 - 255 
    };

    /*
     * ******** D E T E R M I N E W H I C H A L H A B E T ********
     */
    /**
     * Returns one of the _SOMETHING_ALPHABET byte arrays depending on the
     * options specified. It's possible, though silly, to specify ORDERED
     * <b>and</b> URLSAFE in which case one of them will be picked, though there
     * is no guarantee as to which one will be picked.
     */
    private static byte[] getAlphabet(int options)
    {
        if ((options & URL_SAFE) == URL_SAFE)
        {
            return _URL_SAFE_ALPHABET;
        } else if ((options & ORDERED) == ORDERED)
        {
            return _ORDERED_ALPHABET;
        } else
        {
            return _STANDARD_ALPHABET;
        }
    }	// end getAlphabet

    /**
     * Returns one of the _SOMETHING_DECODABET byte arrays depending on the
     * options specified. It's possible, though silly, to specify ORDERED and
     * URL_SAFE in which case one of them will be picked, though there is no
     * guarantee as to which one will be picked.
     */
    private final static byte[] getDecodabet(int options)
    {
        if ((options & URL_SAFE) == URL_SAFE)
        {
            return _URL_SAFE_DECODABET;
        } else if ((options & ORDERED) == ORDERED)
        {
            return _ORDERED_DECODABET;
        } else
        {
            return _STANDARD_DECODABET;
        }
    }	// end getAlphabet

    /**
     * Defeats instantiation.
     */
    private Base64()
    {
    }

    /*
     * ******** E N C O D I N G M E T H O D S ********
     */
    /**
     * Encodes up to the first three bytes of array <var>threeBytes</var> and
     * returns a four-byte array in Base64 notation. The actual number of
     * significant bytes in your array is given by <var>numSigBytes</var>. The
     * array <var>threeBytes</var> needs only be as big as
     * <var>numSigBytes</var>. Code can reuse a byte array by passing a
     * four-byte array as <var>b4</var>.
     *
     * @param b4 A reusable byte array to reduce array instantiation
     * @param threeBytes the array to convert
     * @param numSigBytes the number of significant bytes in your array
     * @return four byte array in Base64 notation.
     * @since 1.5.1
     */
    private static byte[] encode3to4(byte[] b4, byte[] threeBytes, int numSigBytes, int options)
    {
        encode3to4(threeBytes, 0, numSigBytes, b4, 0, options);
        return b4;
    }   // end encode3to4

    /**
     * <p>Encodes up to three bytes of the array <var>source</var> and writes
     * the resulting four Base64 bytes to <var>destination</var>. The source and
     * destination arrays can be manipulated anywhere along their length by
     * specifying <var>srcOffset</var> and <var>destOffset</var>. This method
     * does not check to make sure your arrays are large enough to accomodate
     * <var>srcOffset</var> + 3 for the <var>source</var> array or
     * <var>destOffset</var> + 4 for the <var>destination</var> array. The
     * actual number of significant bytes in your array is given by
     * <var>numSigBytes</var>.</p> <p>This is the lowest level of the encoding
     * methods with all possible parameters.</p>
     *
     * @param source the array to convert
     * @param srcOffset the index where conversion begins
     * @param numSigBytes the number of significant bytes in your array
     * @param destination the array to hold the conversion
     * @param destOffset the index where output will be put
     * @return the <var>destination</var> array
     * @since 1.3
     */
    private static byte[] encode3to4(
            byte[] source, int srcOffset, int numSigBytes,
            byte[] destination, int destOffset, int options)
    {

        byte[] ALPHABET = getAlphabet(options);

        //           1         2         3  
        // 01234567890123456789012345678901 Bit position
        // --------000000001111111122222222 Array position from threeBytes
        // --------|    ||    ||    ||    | Six bit groups to index ALPHABET
        //          >>18  >>12  >> 6  >> 0  Right shift necessary
        //                0x3f  0x3f  0x3f  Additional AND

        // Create buffer with zero-padding if there are only one or two
        // significant bytes passed in the array.
        // We have to shift left 24 in order to flush out the 1's that appear
        // when Java treats a value as negative that is cast from a byte to an int.
        int inBuff = (numSigBytes > 0 ? ((source[ srcOffset] << 24) >>> 8) : 0)
                | (numSigBytes > 1 ? ((source[ srcOffset + 1] << 24) >>> 16) : 0)
                | (numSigBytes > 2 ? ((source[ srcOffset + 2] << 24) >>> 24) : 0);

        switch (numSigBytes)
        {
            case 3:
                destination[ destOffset] = ALPHABET[ (inBuff >>> 18)];
                destination[ destOffset + 1] = ALPHABET[ (inBuff >>> 12) & 0x3f];
                destination[ destOffset + 2] = ALPHABET[ (inBuff >>> 6) & 0x3f];
                destination[ destOffset + 3] = ALPHABET[ (inBuff) & 0x3f];
                return destination;

            case 2:
                destination[ destOffset] = ALPHABET[ (inBuff >>> 18)];
                destination[ destOffset + 1] = ALPHABET[ (inBuff >>> 12) & 0x3f];
                destination[ destOffset + 2] = ALPHABET[ (inBuff >>> 6) & 0x3f];
                destination[ destOffset + 3] = EQUALS_SIGN;
                return destination;

            case 1:
                destination[ destOffset] = ALPHABET[ (inBuff >>> 18)];
                destination[ destOffset + 1] = ALPHABET[ (inBuff >>> 12) & 0x3f];
                destination[ destOffset + 2] = EQUALS_SIGN;
                destination[ destOffset + 3] = EQUALS_SIGN;
                return destination;

            default:
                return destination;
        }   // end switch
    }   // end encode3to4

    /**
     * Performs Base64 encoding on the
     * <code>raw</code> ByteBuffer, writing it to the
     * <code>encoded</code> ByteBuffer. This is an experimental feature.
     * Currently it does not pass along any options (such as
     * {@link #DO_BREAK_LINES} or {@link #GZIP}.
     *
     * @param raw input buffer
     * @param encoded output buffer
     * @since 2.3
     */
    public static void encode(java.nio.ByteBuffer raw, java.nio.ByteBuffer encoded)
    {
        byte[] raw3 = new byte[3];
        byte[] enc4 = new byte[4];

        while (raw.hasRemaining())
        {
            int rem = Math.min(3, raw.remaining());
            raw.get(raw3, 0, rem);
            Base64.encode3to4(enc4, raw3, rem, Base64.NO_OPTIONS);
            encoded.put(enc4);
        }   // end input remaining
    }

    /**
     * Performs Base64 encoding on the
     * <code>raw</code> ByteBuffer, writing it to the
     * <code>encoded</code> CharBuffer. This is an experimental feature.
     * Currently it does not pass along any options (such as
     * {@link #DO_BREAK_LINES} or {@link #GZIP}.
     *
     * @param raw input buffer
     * @param encoded output buffer
     * @since 2.3
     */
    public static void encode(java.nio.ByteBuffer raw, java.nio.CharBuffer encoded)
    {
        byte[] raw3 = new byte[3];
        byte[] enc4 = new byte[4];

        while (raw.hasRemaining())
        {
            int rem = Math.min(3, raw.remaining());
            raw.get(raw3, 0, rem);
            Base64.encode3to4(enc4, raw3, rem, Base64.NO_OPTIONS);
            for (int i = 0; i < 4; i++)
            {
                encoded.put((char) (enc4[i] & 0xFF));
            }
        }   // end input remaining
    }

    /**
     * Serializes an object and returns the Base64-encoded version of that
     * serialized object.
     *
     * <p>As of v 2.3, if the object cannot be serialized or there is another
     * error, the method will throw an java.io.IOException. <b>This is new to
     * v2.3!</b> In earlier versions, it just returned a null value, but in
     * retrospect that's a pretty poor way to handle it.</p>
     *
     * The object is not GZip-compressed before being encoded.
     *
     * @param serializableObject The object to encode
     * @return The Base64-encoded object
     * @throws java.io.IOException if there is an error
     * @throws NullPointerException if serializedObject is null
     * @since 1.4
     */
    public static String encodeObject(java.io.Serializable serializableObject)
            throws java.io.IOException
    {
        return encodeObject(serializableObject, NO_OPTIONS);
    }   // end encodeObject

    /**
     * Serializes an object and returns the Base64-encoded version of that
     * serialized object.
     *
     * <p>As of v 2.3, if the object cannot be serialized or there is another
     * error, the method will throw an java.io.IOException. <b>This is new to
     * v2.3!</b> In earlier versions, it just returned a null value, but in
     * retrospect that's a pretty poor way to handle it.</p>
     *
     * The object is not GZip-compressed before being encoded. <p> Example
     * options:
     * <pre>
     *   GZIP: gzip-compresses object before encoding it.
     *   DO_BREAK_LINES: break lines at 76 characters
     * </pre> <p> Example:
     * <code>encodeObject( myObj, Base64.GZIP )</code> or <p> Example:
     * <code>encodeObject( myObj, Base64.GZIP | Base64.DO_BREAK_LINES )</code>
     *
     * @param serializableObject The object to encode
     * @param options Specified options
     * @return The Base64-encoded object
     * @see Base64#GZIP
     * @see Base64#DO_BREAK_LINES
     * @throws java.io.IOException if there is an error
     * @since 2.0
     */
    public static String encodeObject(java.io.Serializable serializableObject, int options)
            throws java.io.IOException
    {

        if (serializableObject == null)
        {
            throw new NullPointerException("Cannot serialize a null object.");
        }   // end if: null

        // Streams
        java.io.ByteArrayOutputStream baos = null;
        java.io.OutputStream b64os = null;
        java.util.zip.GZIPOutputStream gzos = null;
        java.io.ObjectOutputStream oos = null;


        try
        {
            // ObjectOutputStream -> (GZIP) -> Base64 -> ByteArrayOutputStream
            baos = new java.io.ByteArrayOutputStream();
            b64os = new Base64.OutputStream(baos, ENCODE | options);
            if ((options & GZIP) != 0)
            {
                // Gzip
                gzos = new java.util.zip.GZIPOutputStream(b64os);
                oos = new java.io.ObjectOutputStream(gzos);
            } else
            {
                // Not gzipped
                oos = new java.io.ObjectOutputStream(b64os);
            }
            oos.writeObject(serializableObject);
        } // end try
        catch (java.io.IOException e)
        {
            // Catch it and then throw it immediately so that
            // the finally{} block is called for cleanup.
            throw e;
        } // end catch
        finally
        {
            try
            {
                oos.close();
            } catch (Exception e)
            {
            }
            try
            {
                gzos.close();
            } catch (Exception e)
            {
            }
            try
            {
                b64os.close();
            } catch (Exception e)
            {
            }
            try
            {
                baos.close();
            } catch (Exception e)
            {
            }
        }   // end finally

        // Return value according to relevant encoding.
        try
        {
            return new String(baos.toByteArray(), PREFERRED_ENCODING);
        } // end try
        catch (java.io.UnsupportedEncodingException uue)
        {
            // Fall back to some Java default
            return new String(baos.toByteArray());
        }   // end catch

    }   // end encode

    /**
     * Encodes a byte array into Base64 notation. Does not GZip-compress data.
     *
     * @param source The data to convert
     * @return The data in Base64-encoded form
     * @throws NullPointerException if source array is null
     * @since 1.4
     */
    public static String encodeBytes(byte[] source)
    {
        // Since we're not going to have the GZIP encoding turned on,
        // we're not going to have an java.io.IOException thrown, so
        // we should not force the user to have to catch it.
        String encoded = null;
        try
        {
            encoded = encodeBytes(source, 0, source.length, NO_OPTIONS);
        } catch (java.io.IOException ex)
        {
            assert false : ex.getMessage();
        }   // end catch
        assert encoded != null;
        return encoded;
    }   // end encodeBytes

    /**
     * Encodes a byte array into Base64 notation. <p> Example options:
     * <pre>
     *   GZIP: gzip-compresses object before encoding it.
     *   DO_BREAK_LINES: break lines at 76 characters
     * <i>Note: Technically, this makes your encoding non-compliant.</i>
     * </pre> <p> Example:
     * <code>encodeBytes( myData, Base64.GZIP )</code> or <p> Example:
     * <code>encodeBytes( myData, Base64.GZIP | Base64.DO_BREAK_LINES )</code>
     *
     *
     * <p>As of v 2.3, if there is an error with the GZIP stream, the method
     * will throw an java.io.IOException. <b>This is new to v2.3!</b> In earlier
     * versions, it just returned a null value, but in retrospect that's a
     * pretty poor way to handle it.</p>
     *
     *
     * @param source The data to convert
     * @param options Specified options
     * @return The Base64-encoded data as a String
     * @see Base64#GZIP
     * @see Base64#DO_BREAK_LINES
     * @throws java.io.IOException if there is an error
     * @throws NullPointerException if source array is null
     * @since 2.0
     */
    public static String encodeBytes(byte[] source, int options) throws java.io.IOException
    {
        return encodeBytes(source, 0, source.length, options);
    }   // end encodeBytes

    /**
     * Encodes a byte array into Base64 notation. Does not GZip-compress data.
     *
     * <p>As of v 2.3, if there is an error, the method will throw an
     * java.io.IOException. <b>This is new to v2.3!</b> In earlier versions, it
     * just returned a null value, but in retrospect that's a pretty poor way to
     * handle it.</p>
     *
     *
     * @param source The data to convert
     * @param off Offset in array where conversion should begin
     * @param len Length of data to convert
     * @return The Base64-encoded data as a String
     * @throws NullPointerException if source array is null
     * @throws IllegalArgumentException if source array, offset, or length are
     * invalid
     * @since 1.4
     */
    public static String encodeBytes(byte[] source, int off, int len)
    {
        // Since we're not going to have the GZIP encoding turned on,
        // we're not going to have an java.io.IOException thrown, so
        // we should not force the user to have to catch it.
        String encoded = null;
        try
        {
            encoded = encodeBytes(source, off, len, NO_OPTIONS);
        } catch (java.io.IOException ex)
        {
            assert false : ex.getMessage();
        }   // end catch
        assert encoded != null;
        return encoded;
    }   // end encodeBytes

    /**
     * Encodes a byte array into Base64 notation. <p> Example options:
     * <pre>
     *   GZIP: gzip-compresses object before encoding it.
     *   DO_BREAK_LINES: break lines at 76 characters
     * <i>Note: Technically, this makes your encoding non-compliant.</i>
     * </pre> <p> Example:
     * <code>encodeBytes( myData, Base64.GZIP )</code> or <p> Example:
     * <code>encodeBytes( myData, Base64.GZIP | Base64.DO_BREAK_LINES )</code>
     *
     *
     * <p>As of v 2.3, if there is an error with the GZIP stream, the method
     * will throw an java.io.IOException. <b>This is new to v2.3!</b> In earlier
     * versions, it just returned a null value, but in retrospect that's a
     * pretty poor way to handle it.</p>
     *
     *
     * @param source The data to convert
     * @param off Offset in array where conversion should begin
     * @param len Length of data to convert
     * @param options Specified options
     * @return The Base64-encoded data as a String
     * @see Base64#GZIP
     * @see Base64#DO_BREAK_LINES
     * @throws java.io.IOException if there is an error
     * @throws NullPointerException if source array is null
     * @throws IllegalArgumentException if source array, offset, or length are
     * invalid
     * @since 2.0
     */
    public static String encodeBytes(byte[] source, int off, int len, int options) throws java.io.IOException
    {
        byte[] encoded = encodeBytesToBytes(source, off, len, options);

        // Return value according to relevant encoding.
        try
        {
            return new String(encoded, PREFERRED_ENCODING);
        } // end try
        catch (java.io.UnsupportedEncodingException uue)
        {
            return new String(encoded);
        }   // end catch

    }   // end encodeBytes

    /**
     * Similar to {@link #encodeBytes(byte[])} but returns a byte array instead
     * of instantiating a String. This is more efficient if you're working with
     * I/O streams and have large data sets to encode.
     *
     *
     * @param source The data to convert
     * @return The Base64-encoded data as a byte[] (of ASCII characters)
     * @throws NullPointerException if source array is null
     * @since 2.3.1
     */
    public static byte[] encodeBytesToBytes(byte[] source)
    {
        byte[] encoded = null;
        try
        {
            encoded = encodeBytesToBytes(source, 0, source.length, Base64.NO_OPTIONS);
        } catch (java.io.IOException ex)
        {
            assert false : "IOExceptions only come from GZipping, which is turned off: " + ex.getMessage();
        }
        return encoded;
    }

    /**
     * Similar to {@link #encodeBytes(byte[], int, int, int)} but returns a byte
     * array instead of instantiating a String. This is more efficient if you're
     * working with I/O streams and have large data sets to encode.
     *
     *
     * @param source The data to convert
     * @param off Offset in array where conversion should begin
     * @param len Length of data to convert
     * @param options Specified options
     * @return The Base64-encoded data as a String
     * @see Base64#GZIP
     * @see Base64#DO_BREAK_LINES
     * @throws java.io.IOException if there is an error
     * @throws NullPointerException if source array is null
     * @throws IllegalArgumentException if source array, offset, or length are
     * invalid
     * @since 2.3.1
     */
    public static byte[] encodeBytesToBytes(byte[] source, int off, int len, int options) throws java.io.IOException
    {

        if (source == null)
        {
            throw new NullPointerException("Cannot serialize a null array.");
        }   // end if: null

        if (off < 0)
        {
            throw new IllegalArgumentException("Cannot have negative offset: " + off);
        }   // end if: off < 0

        if (len < 0)
        {
            throw new IllegalArgumentException("Cannot have length offset: " + len);
        }   // end if: len < 0

        if (off + len > source.length)
        {
            throw new IllegalArgumentException(
                    String.format("Cannot have offset of %d and length of %d with array of length %d", off, len, source.length));
        }   // end if: off < 0



        // Compress?
        if ((options & GZIP) != 0)
        {
            java.io.ByteArrayOutputStream baos = null;
            java.util.zip.GZIPOutputStream gzos = null;
            Base64.OutputStream b64os = null;

            try
            {
                // GZip -> Base64 -> ByteArray
                baos = new java.io.ByteArrayOutputStream();
                b64os = new Base64.OutputStream(baos, ENCODE | options);
                gzos = new java.util.zip.GZIPOutputStream(b64os);

                gzos.write(source, off, len);
                gzos.close();
            } // end try
            catch (java.io.IOException e)
            {
                // Catch it and then throw it immediately so that
                // the finally{} block is called for cleanup.
                throw e;
            } // end catch
            finally
            {
                try
                {
                    gzos.close();
                } catch (Exception e)
                {
                }
                try
                {
                    b64os.close();
                } catch (Exception e)
                {
                }
                try
                {
                    baos.close();
                } catch (Exception e)
                {
                }
            }   // end finally

            return baos.toByteArray();
        } // end if: compress
        // Else, don't compress. Better not to use streams at all then.
        else
        {
            boolean breakLines = (options & DO_BREAK_LINES) != 0;

            //int    len43   = len * 4 / 3;
            //byte[] outBuff = new byte[   ( len43 )                      // Main 4:3
            //                           + ( (len % 3) > 0 ? 4 : 0 )      // Account for padding
            //                           + (breakLines ? ( len43 / MAX_LINE_LENGTH ) : 0) ]; // New lines
            // Try to determine more precisely how big the array needs to be.
            // If we get it right, we don't have to do an array copy, and
            // we save a bunch of memory.
            int encLen = (len / 3) * 4 + (len % 3 > 0 ? 4 : 0); // Bytes needed for actual encoding
            if (breakLines)
            {
                encLen += encLen / MAX_LINE_LENGTH; // Plus extra newline characters
            }
            byte[] outBuff = new byte[encLen];


            int d = 0;
            int e = 0;
            int len2 = len - 2;
            int lineLength = 0;
            for (; d < len2; d += 3, e += 4)
            {
                encode3to4(source, d + off, 3, outBuff, e, options);

                lineLength += 4;
                if (breakLines && lineLength >= MAX_LINE_LENGTH)
                {
                    outBuff[e + 4] = NEW_LINE;
                    e++;
                    lineLength = 0;
                }   // end if: end of line
            }   // en dfor: each piece of array

            if (d < len)
            {
                encode3to4(source, d + off, len - d, outBuff, e, options);
                e += 4;
            }   // end if: some padding needed


            // Only resize array if we didn't guess it right.
            if (e <= outBuff.length - 1)
            {
                // If breaking lines and the last byte falls right at
                // the line length (76 bytes per line), there will be
                // one extra byte, and the array will need to be resized.
                // Not too bad of an estimate on array size, I'd say.
                byte[] finalOut = new byte[e];
                System.arraycopy(outBuff, 0, finalOut, 0, e);
                //System.err.println("Having to resize array from " + outBuff.length + " to " + e );
                return finalOut;
            } else
            {
                //System.err.println("No need to resize array.");
                return outBuff;
            }

        }   // end else: don't compress

    }   // end encodeBytesToBytes

    /*
     * ******** D E C O D I N G M E T H O D S ********
     */
    /**
     * Decodes four bytes from array <var>source</var> and writes the resulting
     * bytes (up to three of them) to <var>destination</var>. The source and
     * destination arrays can be manipulated anywhere along their length by
     * specifying <var>srcOffset</var> and <var>destOffset</var>. This method
     * does not check to make sure your arrays are large enough to accomodate
     * <var>srcOffset</var> + 4 for the <var>source</var> array or
     * <var>destOffset</var> + 3 for the <var>destination</var> array. This
     * method returns the actual number of bytes that were converted from the
     * Base64 encoding. <p>This is the lowest level of the decoding methods with
     * all possible parameters.</p>
     *
     *
     * @param source the array to convert
     * @param srcOffset the index where conversion begins
     * @param destination the array to hold the conversion
     * @param destOffset the index where output will be put
     * @param options alphabet type is pulled from this (standard, url-safe,
     * ordered)
     * @return the number of decoded bytes converted
     * @throws NullPointerException if source or destination arrays are null
     * @throws IllegalArgumentException if srcOffset or destOffset are invalid
     * or there is not enough room in the array.
     * @since 1.3
     */
    private static int decode4to3(
            byte[] source, int srcOffset,
            byte[] destination, int destOffset, int options)
    {

        // Lots of error checking and exception throwing
        if (source == null)
        {
            throw new NullPointerException("Source array was null.");
        }   // end if
        if (destination == null)
        {
            throw new NullPointerException("Destination array was null.");
        }   // end if
        if (srcOffset < 0 || srcOffset + 3 >= source.length)
        {
            throw new IllegalArgumentException(String.format(
                    "Source array with length %d cannot have offset of %d and still process four bytes.", source.length, srcOffset));
        }   // end if
        if (destOffset < 0 || destOffset + 2 >= destination.length)
        {
            throw new IllegalArgumentException(String.format(
                    "Destination array with length %d cannot have offset of %d and still store three bytes.", destination.length, destOffset));
        }   // end if


        byte[] DECODABET = getDecodabet(options);

        // Example: Dk==
        if (source[ srcOffset + 2] == EQUALS_SIGN)
        {
            // Two ways to do the same thing. Don't know which way I like best.
            //int outBuff =   ( ( DECODABET[ source[ srcOffset    ] ] << 24 ) >>>  6 )
            //              | ( ( DECODABET[ source[ srcOffset + 1] ] << 24 ) >>> 12 );
            int outBuff = ((DECODABET[ source[ srcOffset]] & 0xFF) << 18)
                    | ((DECODABET[ source[ srcOffset + 1]] & 0xFF) << 12);

            destination[ destOffset] = (byte) (outBuff >>> 16);
            return 1;
        } // Example: DkL=
        else if (source[ srcOffset + 3] == EQUALS_SIGN)
        {
            // Two ways to do the same thing. Don't know which way I like best.
            //int outBuff =   ( ( DECODABET[ source[ srcOffset     ] ] << 24 ) >>>  6 )
            //              | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
            //              | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 );
            int outBuff = ((DECODABET[ source[ srcOffset]] & 0xFF) << 18)
                    | ((DECODABET[ source[ srcOffset + 1]] & 0xFF) << 12)
                    | ((DECODABET[ source[ srcOffset + 2]] & 0xFF) << 6);

            destination[ destOffset] = (byte) (outBuff >>> 16);
            destination[ destOffset + 1] = (byte) (outBuff >>> 8);
            return 2;
        } // Example: DkLE
        else
        {
            // Two ways to do the same thing. Don't know which way I like best.
            //int outBuff =   ( ( DECODABET[ source[ srcOffset     ] ] << 24 ) >>>  6 )
            //              | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
            //              | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 )
            //              | ( ( DECODABET[ source[ srcOffset + 3 ] ] << 24 ) >>> 24 );
            int outBuff = ((DECODABET[ source[ srcOffset]] & 0xFF) << 18)
                    | ((DECODABET[ source[ srcOffset + 1]] & 0xFF) << 12)
                    | ((DECODABET[ source[ srcOffset + 2]] & 0xFF) << 6)
                    | ((DECODABET[ source[ srcOffset + 3]] & 0xFF));


            destination[ destOffset] = (byte) (outBuff >> 16);
            destination[ destOffset + 1] = (byte) (outBuff >> 8);
            destination[ destOffset + 2] = (byte) (outBuff);

            return 3;
        }
    }   // end decodeToBytes

    /**
     * Low-level access to decoding ASCII characters in the form of a byte
     * array. <strong>Ignores GUNZIP option, if it's set.</strong> This is not
     * generally a recommended method, although it is used internally as part of
     * the decoding process. Special case: if len = 0, an empty array is
     * returned. Still, if you need more speed and reduced memory footprint (and
     * aren't gzipping), consider this method.
     *
     * @param source The Base64 encoded data
     * @return decoded data
     * @since 2.3.1
     */
    public static byte[] decode(byte[] source)
            throws java.io.IOException
    {
        byte[] decoded = null;
//        try {
        decoded = decode(source, 0, source.length, Base64.NO_OPTIONS);
//        } catch( java.io.IOException ex ) {
//            assert false : "IOExceptions only come from GZipping, which is turned off: " + ex.getMessage();
//        }
        return decoded;
    }

    /**
     * Low-level access to decoding ASCII characters in the form of a byte
     * array. <strong>Ignores GUNZIP option, if it's set.</strong> This is not
     * generally a recommended method, although it is used internally as part of
     * the decoding process. Special case: if len = 0, an empty array is
     * returned. Still, if you need more speed and reduced memory footprint (and
     * aren't gzipping), consider this method.
     *
     * @param source The Base64 encoded data
     * @param off The offset of where to begin decoding
     * @param len The length of characters to decode
     * @param options Can specify options such as alphabet type to use
     * @return decoded data
     * @throws java.io.IOException If bogus characters exist in source data
     * @since 1.3
     */
    public static byte[] decode(byte[] source, int off, int len, int options)
            throws java.io.IOException
    {

        // Lots of error checking and exception throwing
        if (source == null)
        {
            throw new NullPointerException("Cannot decode null source array.");
        }   // end if
        if (off < 0 || off + len > source.length)
        {
            throw new IllegalArgumentException(String.format(
                    "Source array with length %d cannot have offset of %d and process %d bytes.", source.length, off, len));
        }   // end if

        if (len == 0)
        {
            return new byte[0];
        } else if (len < 4)
        {
            throw new IllegalArgumentException(
                    "Base64-encoded string must have at least four characters, but length specified was " + len);
        }   // end if

        byte[] DECODABET = getDecodabet(options);

        int len34 = len * 3 / 4;       // Estimate on array size
        byte[] outBuff = new byte[len34]; // Upper limit on size of output
        int outBuffPosn = 0;             // Keep track of where we're writing

        byte[] b4 = new byte[4];     // Four byte buffer from source, eliminating white space
        int b4Posn = 0;               // Keep track of four byte input buffer
        int i = 0;               // Source array counter
        byte sbiDecode = 0;               // Special value from DECODABET

        for (i = off; i < off + len; i++)
        {  // Loop through source

            sbiDecode = DECODABET[ source[i] & 0xFF];

            // White space, Equals sign, or legit Base64 character
            // Note the values such as -5 and -9 in the
            // DECODABETs at the top of the file.
            if (sbiDecode >= WHITE_SPACE_ENC)
            {
                if (sbiDecode >= EQUALS_SIGN_ENC)
                {
                    b4[ b4Posn++] = source[i];         // Save non-whitespace
                    if (b4Posn > 3)
                    {                  // Time to decode?
                        outBuffPosn += decode4to3(b4, 0, outBuff, outBuffPosn, options);
                        b4Posn = 0;

                        // If that was the equals sign, break out of 'for' loop
                        if (source[i] == EQUALS_SIGN)
                        {
                            break;
                        }   // end if: equals sign
                    }   // end if: quartet built
                }   // end if: equals sign or better
            } // end if: white space, equals sign or better
            else
            {
                // There's a bad input character in the Base64 stream.
                throw new java.io.IOException(String.format(
                        "Bad Base64 input character decimal %d in array position %d", ((int) source[i]) & 0xFF, i));
            }   // end else: 
        }   // each input character

        byte[] out = new byte[outBuffPosn];
        System.arraycopy(outBuff, 0, out, 0, outBuffPosn);
        return out;
    }   // end decode

    /**
     * Decodes data from Base64 notation, automatically detecting
     * gzip-compressed data and decompressing it.
     *
     * @param s the string to decode
     * @return the decoded data
     * @throws java.io.IOException If there is a problem
     * @since 1.4
     */
    public static byte[] decode(String s) throws java.io.IOException
    {
        return decode(s, NO_OPTIONS);
    }

    /**
     * Decodes data from Base64 notation, automatically detecting
     * gzip-compressed data and decompressing it.
     *
     * @param s the string to decode
     * @param options encode options such as URL_SAFE
     * @return the decoded data
     * @throws java.io.IOException if there is an error
     * @throws NullPointerException if <tt>s</tt> is null
     * @since 1.4
     */
    public static byte[] decode(String s, int options) throws java.io.IOException
    {

        if (s == null)
        {
            throw new NullPointerException("Input string was null.");
        }   // end if

        byte[] bytes;
        try
        {
            bytes = s.getBytes(PREFERRED_ENCODING);
        } // end try
        catch (java.io.UnsupportedEncodingException uee)
        {
            bytes = s.getBytes();
        }   // end catch
        //</change>

        // Decode
        bytes = decode(bytes, 0, bytes.length, options);

        // Check to see if it's gzip-compressed
        // GZIP Magic Two-Byte Number: 0x8b1f (35615)
        boolean dontGunzip = (options & DONT_GUNZIP) != 0;
        if ((bytes != null) && (bytes.length >= 4) && (!dontGunzip))
        {

            int head = ((int) bytes[0] & 0xff) | ((bytes[1] << 8) & 0xff00);
            if (java.util.zip.GZIPInputStream.GZIP_MAGIC == head)
            {
                java.io.ByteArrayInputStream bais = null;
                java.util.zip.GZIPInputStream gzis = null;
                java.io.ByteArrayOutputStream baos = null;
                byte[] buffer = new byte[2048];
                int length = 0;

                try
                {
                    baos = new java.io.ByteArrayOutputStream();
                    bais = new java.io.ByteArrayInputStream(bytes);
                    gzis = new java.util.zip.GZIPInputStream(bais);

                    while ((length = gzis.read(buffer)) >= 0)
                    {
                        baos.write(buffer, 0, length);
                    }   // end while: reading input

                    // No error? Get new bytes.
                    bytes = baos.toByteArray();

                } // end try
                catch (java.io.IOException e)
                {
                    e.printStackTrace();
                    // Just return originally-decoded bytes
                } // end catch
                finally
                {
                    try
                    {
                        baos.close();
                    } catch (Exception e)
                    {
                    }
                    try
                    {
                        gzis.close();
                    } catch (Exception e)
                    {
                    }
                    try
                    {
                        bais.close();
                    } catch (Exception e)
                    {
                    }
                }   // end finally

            }   // end if: gzipped
        }   // end if: bytes.length >= 2

        return bytes;
    }   // end decode

    /**
     * Attempts to decode Base64 data and deserialize a Java Object within.
     * Returns <tt>null</tt> if there was an error.
     *
     * @param encodedObject The Base64 data to decode
     * @return The decoded and deserialized object
     * @throws NullPointerException if encodedObject is null
     * @throws java.io.IOException if there is a general error
     * @throws ClassNotFoundException if the decoded object is of a class that
     * cannot be found by the JVM
     * @since 1.5
     */
    public static Object decodeToObject(String encodedObject)
            throws java.io.IOException, java.lang.ClassNotFoundException
    {
        return decodeToObject(encodedObject, NO_OPTIONS, null);
    }

    /**
     * Attempts to decode Base64 data and deserialize a Java Object within.
     * Returns <tt>null</tt> if there was an error. If <tt>loader</tt> is not
     * null, it will be the class loader used when deserializing.
     *
     * @param encodedObject The Base64 data to decode
     * @param options Various parameters related to decoding
     * @param loader Optional class loader to use in deserializing classes.
     * @return The decoded and deserialized object
     * @throws NullPointerException if encodedObject is null
     * @throws java.io.IOException if there is a general error
     * @throws ClassNotFoundException if the decoded object is of a class that
     * cannot be found by the JVM
     * @since 2.3.4
     */
    public static Object decodeToObject(
            String encodedObject, int options, final ClassLoader loader)
            throws java.io.IOException, java.lang.ClassNotFoundException
    {

        // Decode and gunzip if necessary
        byte[] objBytes = decode(encodedObject, options);

        java.io.ByteArrayInputStream bais = null;
        java.io.ObjectInputStream ois = null;
        Object obj = null;

        try
        {
            bais = new java.io.ByteArrayInputStream(objBytes);

            // If no custom class loader is provided, use Java's builtin OIS.
            if (loader == null)
            {
                ois = new java.io.ObjectInputStream(bais);
            } // end if: no loader provided
            // Else make a customized object input stream that uses
            // the provided class loader.
            else
            {
                ois = new java.io.ObjectInputStream(bais)
                {
                    @Override
                    public Class<?> resolveClass(java.io.ObjectStreamClass streamClass)
                            throws java.io.IOException, ClassNotFoundException
                    {
                        Class c = Class.forName(streamClass.getName(), false, loader);
                        if (c == null)
                        {
                            return super.resolveClass(streamClass);
                        } else
                        {
                            return c;   // Class loader knows of this class.
                        }   // end else: not null
                    }   // end resolveClass
                };  // end ois
            }   // end else: no custom class loader

            obj = ois.readObject();
        } // end try
        catch (java.io.IOException e)
        {
            throw e;    // Catch and throw in order to execute finally{}
        } // end catch
        catch (java.lang.ClassNotFoundException e)
        {
            throw e;    // Catch and throw in order to execute finally{}
        } // end catch
        finally
        {
            try
            {
                bais.close();
            } catch (Exception e)
            {
            }
            try
            {
                ois.close();
            } catch (Exception e)
            {
            }
        }   // end finally

        return obj;
    }   // end decodeObject

    /**
     * Convenience method for encoding data to a file.
     *
     * <p>As of v 2.3, if there is a error, the method will throw an
     * java.io.IOException. <b>This is new to v2.3!</b> In earlier versions, it
     * just returned false, but in retrospect that's a pretty poor way to handle
     * it.</p>
     *
     * @param dataToEncode byte array of data to encode in base64 form
     * @param filename Filename for saving encoded data
     * @throws java.io.IOException if there is an error
     * @throws NullPointerException if dataToEncode is null
     * @since 2.1
     */
    public static void encodeToFile(byte[] dataToEncode, String filename)
            throws java.io.IOException
    {

        if (dataToEncode == null)
        {
            throw new NullPointerException("Data to encode was null.");
        }   // end iff

        Base64.OutputStream bos = null;
        try
        {
            bos = new Base64.OutputStream(
                    new java.io.FileOutputStream(filename), Base64.ENCODE);
            bos.write(dataToEncode);
        } // end try
        catch (java.io.IOException e)
        {
            throw e; // Catch and throw to execute finally{} block
        } // end catch: java.io.IOException
        finally
        {
            try
            {
                bos.close();
            } catch (Exception e)
            {
            }
        }   // end finally

    }   // end encodeToFile

    /**
     * Convenience method for decoding data to a file.
     *
     * <p>As of v 2.3, if there is a error, the method will throw an
     * java.io.IOException. <b>This is new to v2.3!</b> In earlier versions, it
     * just returned false, but in retrospect that's a pretty poor way to handle
     * it.</p>
     *
     * @param dataToDecode Base64-encoded data as a string
     * @param filename Filename for saving decoded data
     * @throws java.io.IOException if there is an error
     * @since 2.1
     */
    public static void decodeToFile(String dataToDecode, String filename)
            throws java.io.IOException
    {

        Base64.OutputStream bos = null;
        try
        {
            bos = new Base64.OutputStream(
                    new java.io.FileOutputStream(filename), Base64.DECODE);
            bos.write(dataToDecode.getBytes(PREFERRED_ENCODING));
        } // end try
        catch (java.io.IOException e)
        {
            throw e; // Catch and throw to execute finally{} block
        } // end catch: java.io.IOException
        finally
        {
            try
            {
                bos.close();
            } catch (Exception e)
            {
            }
        }   // end finally

    }   // end decodeToFile

    /**
     * Convenience method for reading a base64-encoded file and decoding it.
     *
     * <p>As of v 2.3, if there is a error, the method will throw an
     * java.io.IOException. <b>This is new to v2.3!</b> In earlier versions, it
     * just returned false, but in retrospect that's a pretty poor way to handle
     * it.</p>
     *
     * @param filename Filename for reading encoded data
     * @return decoded byte array
     * @throws java.io.IOException if there is an error
     * @since 2.1
     */
    public static byte[] decodeFromFile(String filename)
            throws java.io.IOException
    {

        byte[] decodedData = null;
        Base64.InputStream bis = null;
        try
        {
            // Set up some useful variables
            java.io.File file = new java.io.File(filename);
            byte[] buffer = null;
            int length = 0;
            int numBytes = 0;

            // Check for size of file
            if (file.length() > Integer.MAX_VALUE)
            {
                throw new java.io.IOException("File is too big for this convenience method (" + file.length() + " bytes).");
            }   // end if: file too big for int index
            buffer = new byte[(int) file.length()];

            // Open a stream
            bis = new Base64.InputStream(
                    new java.io.BufferedInputStream(
                    new java.io.FileInputStream(file)), Base64.DECODE);

            // Read until done
            while ((numBytes = bis.read(buffer, length, 4096)) >= 0)
            {
                length += numBytes;
            }   // end while

            // Save in a variable to return
            decodedData = new byte[length];
            System.arraycopy(buffer, 0, decodedData, 0, length);

        } // end try
        catch (java.io.IOException e)
        {
            throw e; // Catch and release to execute finally{}
        } // end catch: java.io.IOException
        finally
        {
            try
            {
                bis.close();
            } catch (Exception e)
            {
            }
        }   // end finally

        return decodedData;
    }   // end decodeFromFile

    /**
     * Convenience method for reading a binary file and base64-encoding it.
     *
     * <p>As of v 2.3, if there is a error, the method will throw an
     * java.io.IOException. <b>This is new to v2.3!</b> In earlier versions, it
     * just returned false, but in retrospect that's a pretty poor way to handle
     * it.</p>
     *
     * @param filename Filename for reading binary data
     * @return base64-encoded string
     * @throws java.io.IOException if there is an error
     * @since 2.1
     */
    public static String encodeFromFile(String filename)
            throws java.io.IOException
    {

        String encodedData = null;
        Base64.InputStream bis = null;
        try
        {
            // Set up some useful variables
            java.io.File file = new java.io.File(filename);
            byte[] buffer = new byte[Math.max((int) (file.length() * 1.4 + 1), 40)]; // Need max() for math on small files (v2.2.1); Need +1 for a few corner cases (v2.3.5)
            int length = 0;
            int numBytes = 0;

            // Open a stream
            bis = new Base64.InputStream(
                    new java.io.BufferedInputStream(
                    new java.io.FileInputStream(file)), Base64.ENCODE);

            // Read until done
            while ((numBytes = bis.read(buffer, length, 4096)) >= 0)
            {
                length += numBytes;
            }   // end while

            // Save in a variable to return
            encodedData = new String(buffer, 0, length, Base64.PREFERRED_ENCODING);

        } // end try
        catch (java.io.IOException e)
        {
            throw e; // Catch and release to execute finally{}
        } // end catch: java.io.IOException
        finally
        {
            try
            {
                bis.close();
            } catch (Exception e)
            {
            }
        }   // end finally

        return encodedData;
    }   // end encodeFromFile

    /**
     * Reads <tt>infile</tt> and encodes it to <tt>outfile</tt>.
     *
     * @param infile Input file
     * @param outfile Output file
     * @throws java.io.IOException if there is an error
     * @since 2.2
     */
    public static void encodeFileToFile(String infile, String outfile)
            throws java.io.IOException
    {

        String encoded = Base64.encodeFromFile(infile);
        java.io.OutputStream out = null;
        try
        {
            out = new java.io.BufferedOutputStream(
                    new java.io.FileOutputStream(outfile));
            out.write(encoded.getBytes("US-ASCII")); // Strict, 7-bit output.
        } // end try
        catch (java.io.IOException e)
        {
            throw e; // Catch and release to execute finally{}
        } // end catch
        finally
        {
            try
            {
                out.close();
            } catch (Exception ex)
            {
            }
        }   // end finally    
    }   // end encodeFileToFile

    /**
     * Reads <tt>infile</tt> and decodes it to <tt>outfile</tt>.
     *
     * @param infile Input file
     * @param outfile Output file
     * @throws java.io.IOException if there is an error
     * @since 2.2
     */
    public static void decodeFileToFile(String infile, String outfile)
            throws java.io.IOException
    {

        byte[] decoded = Base64.decodeFromFile(infile);
        java.io.OutputStream out = null;
        try
        {
            out = new java.io.BufferedOutputStream(new java.io.FileOutputStream(outfile));
            out.write(decoded);
        } // end try
        catch (java.io.IOException e)
        {
            throw e; // Catch and release to execute finally{}
        } // end catch
        finally
        {
            try
            {
                out.close();
            } catch (Exception ex)
            {
            }
        }   // end finally    
    }   // end decodeFileToFile

    /*
     * ******** I N N E R C L A S S I N P U T S T R E A M ********
     */
    /**
     * A {@link Base64.InputStream} will read data from another
     * <tt>java.io.InputStream</tt>, given in the constructor, and encode/decode
     * to/from Base64 notation on the fly.
     *
     * @see Base64
     * @since 1.3
     */
    public static class InputStream extends java.io.FilterInputStream
    {

        private boolean encode;         // Encoding or decoding
        private int position;       // Current position in the buffer
        private byte[] buffer;         // Small buffer holding converted data
        private int bufferLength;   // Length of buffer (3 or 4)
        private int numSigBytes;    // Number of meaningful bytes in the buffer
        private int lineLength;
        private boolean breakLines;     // Break lines at less than 80 characters
        private int options;        // Record options used to create the stream.
        private byte[] decodabet;      // Local copies to avoid extra method calls

        /**
         * Constructs a {@link Base64.InputStream} in DECODE mode.
         *
         * @param in the <tt>java.io.InputStream</tt> from which to read data.
         * @since 1.3
         */
        public InputStream(java.io.InputStream in)
        {
            this(in, DECODE);
        }   // end constructor

        /**
         * Constructs a {@link Base64.InputStream} in either ENCODE or DECODE
         * mode. <p> Valid options:
         * <pre>
         *   ENCODE or DECODE: Encode or Decode as data is read.
         *   DO_BREAK_LINES: break lines at 76 characters
         *     (only meaningful when encoding)</i>
         * </pre> <p> Example:
         * <code>new Base64.InputStream( in, Base64.DECODE )</code>
         *
         *
         * @param in the <tt>java.io.InputStream</tt> from which to read data.
         * @param options Specified options
         * @see Base64#ENCODE
         * @see Base64#DECODE
         * @see Base64#DO_BREAK_LINES
         * @since 2.0
         */
        public InputStream(java.io.InputStream in, int options)
        {

            super(in);
            this.options = options; // Record for later
            this.breakLines = (options & DO_BREAK_LINES) > 0;
            this.encode = (options & ENCODE) > 0;
            this.bufferLength = encode ? 4 : 3;
            this.buffer = new byte[bufferLength];
            this.position = -1;
            this.lineLength = 0;
            this.decodabet = getDecodabet(options);
        }   // end constructor

        /**
         * Reads enough of the input stream to convert to/from Base64 and
         * returns the next byte.
         *
         * @return next byte
         * @since 1.3
         */
        @Override
        public int read() throws java.io.IOException
        {

            // Do we need to get data?
            if (position < 0)
            {
                if (encode)
                {
                    byte[] b3 = new byte[3];
                    int numBinaryBytes = 0;
                    for (int i = 0; i < 3; i++)
                    {
                        int b = in.read();

                        // If end of stream, b is -1.
                        if (b >= 0)
                        {
                            b3[i] = (byte) b;
                            numBinaryBytes++;
                        } else
                        {
                            break; // out of for loop
                        }   // end else: end of stream

                    }   // end for: each needed input byte

                    if (numBinaryBytes > 0)
                    {
                        encode3to4(b3, 0, numBinaryBytes, buffer, 0, options);
                        position = 0;
                        numSigBytes = 4;
                    } // end if: got data
                    else
                    {
                        return -1;  // Must be end of stream
                    }   // end else
                } // end if: encoding
                // Else decoding
                else
                {
                    byte[] b4 = new byte[4];
                    int i = 0;
                    for (i = 0; i < 4; i++)
                    {
                        // Read four "meaningful" bytes:
                        int b = 0;
                        do
                        {
                            b = in.read();
                        } while (b >= 0 && decodabet[ b & 0x7f] <= WHITE_SPACE_ENC);

                        if (b < 0)
                        {
                            break; // Reads a -1 if end of stream
                        }   // end if: end of stream

                        b4[i] = (byte) b;
                    }   // end for: each needed input byte

                    if (i == 4)
                    {
                        numSigBytes = decode4to3(b4, 0, buffer, 0, options);
                        position = 0;
                    } // end if: got four characters
                    else if (i == 0)
                    {
                        return -1;
                    } // end else if: also padded correctly
                    else
                    {
                        // Must have broken out from above.
                        throw new java.io.IOException("Improperly padded Base64 input.");
                    }   // end 

                }   // end else: decode
            }   // end else: get data

            // Got data?
            if (position >= 0)
            {
                // End of relevant data?
                if ( /*
                         * !encode &&
                         */position >= numSigBytes)
                {
                    return -1;
                }   // end if: got data

                if (encode && breakLines && lineLength >= MAX_LINE_LENGTH)
                {
                    lineLength = 0;
                    return '\n';
                } // end if
                else
                {
                    lineLength++;   // This isn't important when decoding
                    // but throwing an extra "if" seems
                    // just as wasteful.

                    int b = buffer[ position++];

                    if (position >= bufferLength)
                    {
                        position = -1;
                    }   // end if: end

                    return b & 0xFF; // This is how you "cast" a byte that's
                    // intended to be unsigned.
                }   // end else
            } // end if: position >= 0
            // Else error
            else
            {
                throw new java.io.IOException("Error in Base64 code reading stream.");
            }   // end else
        }   // end read

        /**
         * Calls {@link #read()} repeatedly until the end of stream is reached
         * or <var>len</var> bytes are read. Returns number of bytes read into
         * array or -1 if end of stream is encountered.
         *
         * @param dest array to hold values
         * @param off offset for array
         * @param len max number of bytes to read into array
         * @return bytes read into array or -1 if end of stream is encountered.
         * @since 1.3
         */
        @Override
        public int read(byte[] dest, int off, int len)
                throws java.io.IOException
        {
            int i;
            int b;
            for (i = 0; i < len; i++)
            {
                b = read();

                if (b >= 0)
                {
                    dest[off + i] = (byte) b;
                } else if (i == 0)
                {
                    return -1;
                } else
                {
                    break; // Out of 'for' loop
                } // Out of 'for' loop
            }   // end for: each byte read
            return i;
        }   // end read
    }   // end inner class InputStream

    /*
     * ******** I N N E R C L A S S O U T P U T S T R E A M ********
     */
    /**
     * A {@link Base64.OutputStream} will write data to another
     * <tt>java.io.OutputStream</tt>, given in the constructor, and
     * encode/decode to/from Base64 notation on the fly.
     *
     * @see Base64
     * @since 1.3
     */
    public static class OutputStream extends java.io.FilterOutputStream
    {

        private boolean encode;
        private int position;
        private byte[] buffer;
        private int bufferLength;
        private int lineLength;
        private boolean breakLines;
        private byte[] b4;         // Scratch used in a few places
        private boolean suspendEncoding;
        private int options;    // Record for later
        private byte[] decodabet;  // Local copies to avoid extra method calls

        /**
         * Constructs a {@link Base64.OutputStream} in ENCODE mode.
         *
         * @param out the <tt>java.io.OutputStream</tt> to which data will be
         * written.
         * @since 1.3
         */
        public OutputStream(java.io.OutputStream out)
        {
            this(out, ENCODE);
        }   // end constructor

        /**
         * Constructs a {@link Base64.OutputStream} in either ENCODE or DECODE
         * mode. <p> Valid options:
         * <pre>
         *   ENCODE or DECODE: Encode or Decode as data is read.
         *   DO_BREAK_LINES: don't break lines at 76 characters
         *     (only meaningful when encoding)</i>
         * </pre> <p> Example:
         * <code>new Base64.OutputStream( out, Base64.ENCODE )</code>
         *
         * @param out the <tt>java.io.OutputStream</tt> to which data will be
         * written.
         * @param options Specified options.
         * @see Base64#ENCODE
         * @see Base64#DECODE
         * @see Base64#DO_BREAK_LINES
         * @since 1.3
         */
        public OutputStream(java.io.OutputStream out, int options)
        {
            super(out);
            this.breakLines = (options & DO_BREAK_LINES) != 0;
            this.encode = (options & ENCODE) != 0;
            this.bufferLength = encode ? 3 : 4;
            this.buffer = new byte[bufferLength];
            this.position = 0;
            this.lineLength = 0;
            this.suspendEncoding = false;
            this.b4 = new byte[4];
            this.options = options;
            this.decodabet = getDecodabet(options);
        }   // end constructor

        /**
         * Writes the byte to the output stream after converting to/from Base64
         * notation. When encoding, bytes are buffered three at a time before
         * the output stream actually gets a write() call. When decoding, bytes
         * are buffered four at a time.
         *
         * @param theByte the byte to write
         * @since 1.3
         */
        @Override
        public void write(int theByte)
                throws java.io.IOException
        {
            // Encoding suspended?
            if (suspendEncoding)
            {
                this.out.write(theByte);
                return;
            }   // end if: supsended

            // Encode?
            if (encode)
            {
                buffer[ position++] = (byte) theByte;
                if (position >= bufferLength)
                { // Enough to encode.

                    this.out.write(encode3to4(b4, buffer, bufferLength, options));

                    lineLength += 4;
                    if (breakLines && lineLength >= MAX_LINE_LENGTH)
                    {
                        this.out.write(NEW_LINE);
                        lineLength = 0;
                    }   // end if: end of line

                    position = 0;
                }   // end if: enough to output
            } // end if: encoding
            // Else, Decoding
            else
            {
                // Meaningful Base64 character?
                if (decodabet[ theByte & 0x7f] > WHITE_SPACE_ENC)
                {
                    buffer[ position++] = (byte) theByte;
                    if (position >= bufferLength)
                    { // Enough to output.

                        int len = Base64.decode4to3(buffer, 0, b4, 0, options);
                        out.write(b4, 0, len);
                        position = 0;
                    }   // end if: enough to output
                } // end if: meaningful base64 character
                else if (decodabet[ theByte & 0x7f] != WHITE_SPACE_ENC)
                {
                    throw new java.io.IOException("Invalid character in Base64 data.");
                }   // end else: not white space either
            }   // end else: decoding
        }   // end write

        /**
         * Calls {@link #write(int)} repeatedly until <var>len</var> bytes are
         * written.
         *
         * @param theBytes array from which to read bytes
         * @param off offset for array
         * @param len max number of bytes to read into array
         * @since 1.3
         */
        @Override
        public void write(byte[] theBytes, int off, int len)
                throws java.io.IOException
        {
            // Encoding suspended?
            if (suspendEncoding)
            {
                this.out.write(theBytes, off, len);
                return;
            }   // end if: supsended

            for (int i = 0; i < len; i++)
            {
                write(theBytes[ off + i]);
            }   // end for: each byte written

        }   // end write

        /**
         * Method added by PHIL. [Thanks, PHIL. -Rob] This pads the buffer
         * without closing the stream.
         *
         * @throws java.io.IOException if there's an error.
         */
        public void flushBase64() throws java.io.IOException
        {
            if (position > 0)
            {
                if (encode)
                {
                    out.write(encode3to4(b4, buffer, position, options));
                    position = 0;
                } // end if: encoding
                else
                {
                    throw new java.io.IOException("Base64 input not properly padded.");
                }   // end else: decoding
            }   // end if: buffer partially full

        }   // end flush

        /**
         * Flushes and closes (I think, in the superclass) the stream.
         *
         * @since 1.3
         */
        @Override
        public void close() throws java.io.IOException
        {
            // 1. Ensure that pending characters are written
            flushBase64();

            // 2. Actually close the stream
            // Base class both flushes and closes.
            super.close();

            buffer = null;
            out = null;
        }   // end close

        /**
         * Suspends encoding of the stream. May be helpful if you need to embed
         * a piece of base64-encoded data in a stream.
         *
         * @throws java.io.IOException if there's an error flushing
         * @since 1.5.1
         */
        public void suspendEncoding() throws java.io.IOException
        {
            flushBase64();
            this.suspendEncoding = true;
        }   // end suspendEncoding

        /**
         * Resumes encoding of the stream. May be helpful if you need to embed a
         * piece of base64-encoded data in a stream.
         *
         * @since 1.5.1
         */
        public void resumeEncoding()
        {
            this.suspendEncoding = false;
        }   // end resumeEncoding
    }   // end inner class OutputStream
}   // end class Base64
